Ambulance bed rest



June 21, .1932. H. c. M DOUGALL 1,864,454

AMBULANCE BED REST Filed June 14,1929 3 Sheets-Sheet l INVENTOR'.

ATTORNEY- WITNESS. 2 i

June 21, 1932. H. c. M DOUGALL AMBULANCE BED REST Filed June 14, 1929 3Sheets-Sheet 2' Ill/III I I I :22. I

. INVENTOR. BY 2 WITNESS:

AITORNEY.

June 21, 1932. H c. M DOUGALL 1,864,454

AMBULANCE BED REST Filed June 14, 1929 3 Sheets-Sheet s INVENTORZ ATTORNEY.

WITNESS: g

Patented June 21, 1932 i g p 1 UITED STATES PATENT OFFICE A HOWARD o.MAcDoUeALL, or NEw YORK, N. Y.

AMBULANCE nn'nnnsr Application filed june 14, 1929; Serial No. 370,972.

This invention relates to improvements in illustrating in dotted linesthe position of one ambulance bed rests. v of the pneumatic jacks in anupset position. The primary object of the invention resides Figure 1 isan enlarged vertical longitudiin a cushioning or shock absorbing meansfor nal sectional View on the line H of F ig- 5. ambulance cots or beds,for supporting the cot ure 3. 55 or bed above the floor of an ambulancefor Figure 5 is a vertical sectional view on the arresting any shockwhich may be caused by line 55 of Figure 4. the vehicle passing over anuneven street or F'gure 6 is a horizontal sectional view on road, toassure comfort of a sick or injured the line 6 6 of Figure 4.

1o person lying upon the cot. Figure 7 is a perspective view of myinven- I 7 Another object of the invention is to protion per se. videpneumatic jacks upon the floor of an Figure 8 is a sectional viewthrough the ambulanceonto which the cot may be rolled air control valve.or placed, and which jacks may be raised to Referring to the drawings byreference .support the cot with its legs or wheels above characters, thenumeral 10 designates one of 65 the floor, the said jacks acting as.shock abmy improved pneumatic jacks or shock absorbers for arresting anyunevenmovement' sorbers, four of which are arranged in suit of theambulance while in motion. able spaced relation upon the floor 11 of anA further object of the invention is the pro ambulance body 12. Each ofthe jacks 10 20, vision of an ambulance having four pneuincludesastationary cylinder 12 .mounted 7o matic jacks mounted (on the floorthereof upon a base 13, the base of each jack being which may besimultaneously raised by the hingedly mounted to thefioor 11 as'at lt-so pumping of air under pressure into anequalthat each jack may swingfrom a vertical izing pressure tank, all of the jacksreceiving positiontoan upset position in the direction their air from the common tank, andwhich of therear'doors 15 of the body. Telescop- 7 tank is filled by ahand pump conveniently ingthe stationary cylinder 12 is a movablelocated in reach of the operator or driver of cylinder 16, the outer endof the same being the ambulance. Y i 7 provided with a cap 17 having aseat 18 A further object of the invention is to proprovided in. spacedlugs 19 formed on said vide a hand control valve in the air line Sys:cap. 2 1 p tem to control the filling of the system with Theouter end ofthe stationary cylinder 12 compressed air to raise the respective jacks,is provided with a central opening 20. and and for bleeding the systemof air to allow supports an upstanding collar 21 which surthe jacks toreturn to a lowered position. v rounds the opening 20, while clamped be-With these and other objects in view, the tween thefiange and the collar21 on the 35 invention resides in certain novel construc 1 outer end ofsaid cylinder is a leatherwasher tion and combination and arrangement aof 22 whichis held against the inner walls of the parts, the essentialfeatures of which are movable cylinder 16 byfiat springs 23wherehereinafter fully described, are particularlyby to provide a sealedjoint between the tele- 49 ointed out in the appended claim, and arescoping cylinders. Bolts or screws 2 1pass19c lllustrated in theaccompanying drawings, in through the flanges of the collar 21 and whicha through the leather washer 22 and through Figure 1 is a side elevationshowing an" the outerend of the stationary cylinder. automobileambulance equipped with my in .A screwjplug 25 is threaded into the base'j vention. 13-aXially thereof and has its inner endpro- 9 Figure 2 is ahorizontal sectional view vid'edwith an eye 26 to which a ring, 27 is.through the body of the ambulance. f connected. A substantiallyiV-shapedmem- Figure 3 is an enlarged vertical sectional ber 28;,is connectedtothe eye 27 and which View on the line 33 of Figure'2 but showing.member is formed of. a single piece of mateanambulance cot, in asupported position, and i rialhavingits ends bentinto hooks 29, whicn10o simultaneously to free ends of the inverted V-shaped'member 34 areprovided with hooks 36 which act as seats for the lower end of thespring 30. In this construction, it will be seen that the members 38 and34 act as ties between the two telescoping cylinders and the contractilespring 30 acts to hold the movable cylinder 16 in re tracted positionwith respect to the stationary cylinder 12. The interior of thecylinders are filled with oil as shown in Figures 4 and 5 of thedrawings, the level of which terminates approximately at the top of thecollar 21 and above the washer 22 to positively seal the joint betweenthe walls of the two telescoping cylinders and the space above the levelof the oil within the movable cylinder 16 constitutes an air chamber 37.

Provided in the cap 17 is an air inlet and outlet 38 in'which a gravitycheck valve 39 is mounted. From the description thus far, it will benoted that ifair under pressure is introduced into the air chamber 37 toovercome the tension of the spring 30, the movable cylinder 16 willmove'to an extended position and that if air is bled from the' airchamber, the spring 30 will tend to lower or retract the movablecylinder with respect to the stationary cylinder.

Mounted to the chassis ofthe ambulance or body is an air equalizing ordistributing tank 40 to which the four j a'cks 10'are connected byflexible tubes or hose 41, the said hose leading to the air inlet andoutlet ports 38 of the respective jacks. A hose or air line 42 leadsfrom the tank 40 to a hand pump 43 which may be mounted upon the instrument board or any othersuitable place within reach of the operator ofthe ambulance whereby air may be pumped under pressure to thetank 40from where it is distributed the respective jacks through the tubes 41in order that an equal amount of air simultaneously enters the airchambers 37 of thejacks in order to raise them at the same rate ofspeed. Arranged in the hose 42 is an air pressure gauge 44 which mayalsobe mounted on the instrument board in order that the operator mayknow the amount of air pressure in the system. Also mounted in the airline 42 is an air control valve 45 having a manually turnable plug; 46provided with a three-way passage 47 inorder that'air from the pump '43may pass directly through the air line 42 to t he l? tank 40 or'bymanip'ulation of the plug, the

line 42 may be brought into communication with a bleed outlet 48provided in the valve in order to bleed the system of air pressure whendesired to lower the jacks by releasing the air from the air chambers37.

Assume that the jacks are in a lowered position and it is desired toraise the same to support an ambulance wheel bed 49 above the floor 11of the ambulance body. The bed 49 with its occupant is rolled onto thefloor 11 of the body until the transverse bars 50 are :in alignment withthe seats of the front and rear sets of the jacks.

The operator then proceeds to actuate the hand pump 43, the valve 45being in a position so that the air from the pump passes through the airline 42 to the tank 40 from where it is distributed through the flexiblehose 41 to the air chambers 37 of the respective jacks. is pumped intothe system toactuate the movable cylinders 16 in order to raisethewheels of the ambulance bed above the'level of the floor as shown indotted linesin Figure 3 of the drawings' The amount of air necessary toraise the jacks with the bed supported thereon, is of course, dependentupon the weight of the occupant of the bed. It will now be seen that anyvibration of the ambulance body during travel of the ambulance will betaken up'by these pneumatic jacks which in turn act in the capacity ofshock absorbers. In turning right orleft, the tendency of one side ofthe ambulance bed to move downward is prevented by the check valves 39as any increased pressure by the downward movement of the-movable cylin-To remove the ambulance bed 49, the same may be lifted from theseats 18and the jacks upset as shown indotted lines in Figure 3 whereupon thewheels of the bed may be lowered onto the floor of the body and the bedrolled rearwardly'. I have found it unnecessary to bleed the systemafter each use as the jacks may beset up in a vertical position with theair remaining therein and the ambulance bed replaced'upon the seats.However, the air pressure may be reduced from the system in the eventthat the occupant of the bed is of a lighter weight than the occupantpreviously supported and for this purpose, the valve 45 may be actuatedso that the threeway port 47 registers with the bleed port 48 and withthe air line 42. Only a small amount of air is capable of beingexhausted from the system during each actuation of the valve,therefore,the valve must be turned on or oflto such positiondue to the fact thatthe check valve has a tendency to check the flow of air from therespective air chambers. 37. The air pressure being'equal on oppositesides of the ball of the check valve, the said Suflicient air and theoutward rush of air through the port 38 tends to close the valve, thusby turning on and oil of the valve 45, the system may be graduallyexhausted of air when required but as before stated, it is unnecessaryto bleed the system during use of the jacks.

While I have described what I deem to be the most desirable embodimentof my invention, it is obvious that many of the details may be variedwithout in any way departing from the spirit of my invention, and Itherefore do not limit myself to the exact details of constructionherein set forth nor to anything less than the whole of my inventionlimited only by the appended claim.

What is claimed as new is In a pneumatic jack comprising an outer hollowcylinder having a head, a second hollow cylinder having a closed baseanda top annular inwardly projecting horizontal flange, said secondcylinder being slidable relative to the first cylinder and there beingan air chamber within the cylinders, said chamber having also therein alubricating liquid, a yieldable washer having one flange positioned onsaid first flange and having a vertical flange disposed in contactingrelation with the inner periphery of the outer.

cylinder, spring means retaining said vertical flange in position, arigid annular flange positioned on said first yieldable flange,fastening elements maintaining said latter flange and said first flangein tight relation with said first yieldable flange, and a secondvertical flange rising from said rigid flange and extending higher thanthe top of said first vertical flange, thereby providing a space betweensaid second vertical flange and the inner periphery of said outercylinder for housing part of the liquid to facilitate relative movementof the cylinders, said lubricatin g liquid extending above the verticalflange of said washer to seal the joint between the cylinders, saidhollow cylinders having opposed closed ends, said cylinders having anair chamber therein, a ring on each of said ends in said chamber, anelongate member supported at one of its terminals on one of said ringsand having a pair of hooks adjacent the other ring, another elongatemember supported at one of its terminals on said latter ring and havinga pair of hooks adjacent the first mentioned terminal of said firstelongate member, and a helical coil spring carried on said members'andhaving its opposed end coils in the terminal hooks of said respectivemembers for resilinetly resisting air pressure in said chamber duringreciprocation of said cylinders.

In testimonywhereof I have aflixed my signature.

HOWARD C. MAGD OUGALL.

